Testing apparatus



March 13, 1945. F, SHORT 2,371,192 TESTING APPARATUS Filed July 31, 1942 Frank fihurt result is that it becomes Patented Mar. 13, 1945' Fl-m Short, United States Army,

Canton Center, Conn. V 7 Application July 31, 1942, Serial No. 453,144 3 Claims. (Cl. 177-311) (Granted under the act of March amended April 30, I928; 370 0.

The invention described herein may be manuiactured and used by or for the Government for governmental purposes, without the payment to me o1v any royalty thereon.

This invention relates to testing apparatus, particularly to testing as applied to a fuse train during the powder loading process.

In the processor machine loading powder into a fuse train, it sometimes happens that the powder nozzle clogs for a time, with the result that no powder is loaded into the fuse even though manufacture oi the fiber fuse cover continues. The

diflicult to detect what part of the fuse train is loaded and what part is not.

It is the object of this invention to provide a testing device which makes detection of unloaded fuse trains easy. The loading machine feeds as the fiber is being wave energy is directed toward the powder path and, if no powder is passing through the nozzle, continues across the powder path to a light sensitive relay which opcrates a signal means to indicate that the fuse train is not being loaded.

The specific nature of the invention as well as other advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Fig. 1 of the drawing shows one embodiment of the invention, with parts broken away and in section.

Fig. 2 is a top view of a portion of the system of Fig. 1. For simplicity, the nozzle is shown empty in this figure.

Fig. 3 is a view of part of a system similar to that of Fig. 1, but showing'a modification.

Referring to the drawing in detail, at 2 is shown part of a powder source which feeds the powder to a nozzlel. Nozzl 4 is provided with a powder path which preferably consists of a longitudinal bore 6 gradually diminishing in diameter from the powder entrance end to give a funnel eflect. When there is no powder in the bore, the nozzle has a light path through it across the powder path. This light path is indicated by the dotdash line 2:, which is shown as completed in order to indicate the light path in its entirety, even though the passage of light is actually blocked when powder passes in an unbroken stream through bore 6.

3, 1883, as G. 757) Nozzle 4 is preferably divided substantially on 2. To prevent the made in two parts, being a diameter, as shown in to pass. I 0, Fig- 1.

As the powder leaves the exit end of nozzle 4, it passes into the cover (2 which is being twisted as it is loaded. Two of the yarn strands going to make up cover i2 are indicated at M. Inasmuch as the cover twisting machine per se forms no part of this invention, the machine is not shown.

Wav energy, such as light, may be provided for passage through the nozzle by any suitable source, such as light bulb l6 which receives its energy from a power source (not shown) through lines [8 and resistance 20. The light from bulb I 6 is collected by condensing lens 22 which transmits it to colllmating lens 24 in stantially parallel light may be directed into nozzle l.

Nozzle I is preferably made of any suitable transparent material, such as glass or one of the transparent resins or plastics available. If desired, th place at which the narrow beam of light enters nozzle 4 may be flattened, to eliminate refraction. The four reflecting surfaces inside the nozzle may be similarly treated to prevent or decrease dispersion. At the other side of the powder path, in position to receive light which passes through the nozzl when there is no powder in bore 6 to impede it, is a light sensitive means such as photoelectric cell 26. A lens 28 may be provided to collect the light leaving the nozzle to transmit it to the cell 26.

Cell 25 may be any suitable relay sensitive to the kind of wave energy used. Where ordinary light is used, cell 25 may be a photoelectric or photoemissive tube, or it may be a photovoltaic cell, of the wet or barrier layer type. These are usually grouped indiscriminately under the term photoelectric cell. Whatever type of relay is used, its output may be magnified in amplifier 30 which takes its power from lines is. The output of the amplifier may be utilized in any of a number of ways, or incombinations thereof. For example, the power output of amplifier 30 may be used to which forms the all of those things In the application of the invention illustrated. a

order that sub-.

paint spotting mechanism is used to mark that part of the fuse cover which has no powder in it. This is accomplished by a solenoid 32 which is energized when light strikes the sensitive element of cell 26. A movable-armature 34 carries a piston 36 of a simple pump operating to deposit paint through tip 38 from reservoir 40 upon fuse cover l2. An interrupter 42 is placed in the amplifiersolenoid circuit to break the circuit so that it may immediately be reestablished if light is stil1 passing to cell 26. In this manner, means are provided to keep the paint pump operating so long as there is no powder flowing through nozzle 4. Tip 38 will preferably be small enough so that paint will be prevented from dripping out by surface tension while piston 36 is withdrawn.

In order todecrease the tendency of the powder to clog in its passage through the nozzle, a vibrator 43 may be provided to continuously agitate the nozzle. Vibrator 43 may be any of a suitable type, but is shown in the drawing as being electrical, receiving power from lines l8.

In the modification of Fig. 3, a powder nozzle 4' has recesses 44 cut to permit ray 2: to take a more direct path through nozzle 4'. Wave energy source l6, lenses 22, 24 and 28, and cell 26 may be similar to, or the same as, those elements in Figs. 1 and 2. Where it is feasible to .use the embodiment of Fig. 3, it will be found to be considerably simpler.

Operation-So long as powder flowsthrough bore 6, the passage of light to the photoelectric cell is blocked. However, if bore 6 becomes clogged in its tapering portion, the portion below will empty, and light from bulb IE will reach cell 26. Solenoid 32 will thereupon be energized, actuating piston 36 to eject a spot of paint upon cover l2. Interrupter 42 breaks the circuit, restoring piston 36 to the position shown in Fig. 1 under the influence of the spring. If the ='clog in then be made merely by looking for the paint spots.

I claim:

1. Testing apparatus comprising a cylindrical transparent powder dispenser having conical aurface ends,-a powder passage through the cylinder from end to end, means to direct light wave energy through the dispenser across the powder passage, energy sensitive means positioned to receive the wave energy from the dispenser, signal means connected to receive impulses from the energy sensitive means, said dispenser being split along the axis of the powder passage, the surfaces of the split being coated with an opaque paint, and the plane of the split being across the direction of the wave energy passing through the dispenser.

2. The apparatus of claim 1, characterized in that there is an opaque coating on the powder passage except for that portion intended to permit the passage of the light wave energy.

3. In a fuse-loading machine, a transparent powder nozzle formed with an interior cone shaped receiving end presenting opposite inward- 1y inclined reflecting surfaces and similarly inclined outer surfaces adjacent its lower end whereby a light path is formed extending substantially throughout the entire length of the nozzle, and a powder conduit extending through the nozzle, means for directing a light beam into said'nozzle against certain of said opposite inwardly inclined reflecting surfaces for reflection lengthwise of said nozzle to follow said light path and a light sensitive means along the light path adapted .to receive the light which has passed through the nozzle.

Q FRANK SHORT. 

